Reading incoming packets using a raw socket on IP protocol in C#

Question

I'm trying to read incoming packets on a raw socket with headers enabled. Looking at other projects, such as MJsniffer on CodeProject I've been able to create my own code to read everything I want. The problem: I'm only retrieving information that is OUTGOING. Here's my code to initialize a raw socket, the processing code is irrelevant at this point..

// Resolve the host name or IP address to am IPHostEntry instance
IPHostEntry hIPHostEntry = Dns.GetHostEntry( Dns.GetHostName());

// Initialize a new instance of the Socket class.
Socket hSocket = new Socket( AddressFamily.InterNetwork, SocketType.Raw, ProtocolType.Unspecified ); // IP is possible.

// Bind the socket to each resolved IP address.
foreach ( IPAddress hIPAddress in hIPHostEntry.AddressList ) try { hSocket.Bind( new IPEndPoint( hIPAddress, 0 )); } catch( Exception ) { continue; }

// Configure the incoming socket to accept all the required information.
hSocket.SetSocketOption( SocketOptionLevel.IP, SocketOptionName.HeaderIncluded, true );

// Configure the incoming socket to receive all the required information.
hSocket.IOControl( IOControlCode.ReceiveAll, BitConverter.GetBytes( 1 ), BitConverter.GetBytes( 1 ));

// Return the configured socket.
return hSocket;

Running on Windows 7 64-Bit, I have full Administrative rights, how can I modify this code to get a socket able to read incoming packets? Outgoing is nice, and I need that too, but I absolutely need incoming packets as well.

PS: I don't want to force users to install WinPcap. I don't want to capture or spoof or anything, just read, this SHOULD be possible..

Answer 1

This may no longer help you, but for anyone else:

After spending too much time looking at this myself, I ran the executable by itself instead of through Visual Studio. Incoming traffic, amazing. I then added the VS debug.exe (MJSniff.vshost.exe) to the allowed programs in my firewall and that works now as well. (It's always the simple things...)

Edit: credit also to an answer here by Joe Mattioni: Unable to read incoming responses using raw sockets

Answer 2

For debugging purposes, have you tried binding to IPAddress.Any instead? This way, you will have one single binding to all local interfaces.

Also, are you using Receive() or ReceiveFrom() , it should be ReceivedFrom() for connectionless sockets.